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A27M Cruiser Tank Mk. VIII Cromwell
}} The A27M Cruiser Tank Mk VIII Cromwell 'was a cruiser tank used by Great Britain in World War II. Description The Cromwell was a very fast and maneuverable Cruiser Tank.http://www.militaryfactory.com/armor/detail.asp?armor_id=67 The Cromwell was developed from the A24 Cruiser Tank Mk. VII Cavalier and the A27L Cruiser Tank Mk. VIII Centuar except it was fitted with a new Rolls Royce Meteor Engine (Thus it was called the A27M, with the M standing for Meteor). The engine is just a variant of the Rolls Royce Merlin engine which powered aircraft like the Supermarine Spitfire. It was much better than its predecessors in that it was more reliable than cruiser tanks before it. It had a maximum of 76mm of armor in the front of the turret, with 51mm of armor on the sides, and 44mm on the rear of the turret. On the hull, there is only 64mm of armor on the front, 29-44mm on the sides, and 25mm of rear armor on the hull. This tank only weighs 28 tonnes. A total of 4,016 Cromwells were produced between 1944 and 1955. 3,066 of these were produced during the war itself.http://warfarehistorynetwork.com/daily/wwii/ww2-vehicles-the-british-cromwell-tank/ A number of countries had Cromwells in service during World War II, they included: *Great Britain *Portugal *Poland *Israel *Greece *Finland *Czechoslovakia The A34 Cruiser Tank Mk. X Comet was based on the hull of a Cromwell tank. Variants The Cromwell had a few variants of the main tank. Most variants were just converted from A27L Cruiser Tank Mk. VIII Centuar to the Cromwell. http://www.tanks-encyclopedia.com/ww2/gb/A27M_Cruiser_MkVIII_Cromwell.php *'Cromwell I: A Centaur I with an early V12 Meteor engine. Produced with the Ordnance QF 6-pounder gun (57 mm). *'Cromwell II:' This was only a concept, they had a wider track width (from 14in to 15.5 in), and removing the hull mounted 7.92 mm BESA Machine Gun to increase storage. *'Cromwell III:' Converted Centaur I's with the early V12 Meteor Engine. *'Cromwell IV:' This variant of Cromwell was the most widely produced of all the variants. This model of Cromwell had a new V12 Meteor engine and a re-chambered 6-pounder gun as a 75 mm gun. *'Cromwell IVw:' This variant of Cromwell had the modifications as the Cromwell IV but the hull was welded instead of riveted (Thus the 'w' in the name). *'Cromwell Vw:' A model of Cromwell which was produced with a welded hull and a 75 mm gun from the start. *'Cromwell VI:' New main armament, 95 mm Howitzer. Used as a close support tank that carries smoke and HE rounds. *'Cromwell VII:' Late variant, had additional armour (101 mm on the front flat plate), wider tracks (15.5 in), an additional gearbox, and a larger turret ring. Many Cromwell IV's and V's had been converted to this model of Cromwell. *'Cromwell VIIw:' Reworked from Cromwell Vw to fit Cromwell VII modifications and a welded hull *'Cromwell VIII:' Reworked Cromwell VIs with Cromwell VIIs upgrades. The hull of the Cromwell was changed over the time it was produced: *'Hull Type A:' Driver and Hull Machine Gunner had lift up "suicide" hatches similar to the Cavalier. These could be blocked by the turret, preventing emergency egress. *'Hull Type B:' Hull Machine Gunner's hatch changed to a side opening safety hatch. The number of track-guard bins is reduced from 4 to 3 to make way for the hatch. *'Hull Type C:' Air inlet redesigned to trapezoid shape. Introduction of Valentine type (rack and pawl) eccentric axle. *'Hull Type D:' Engine deck reworked to provide easy access to radiators. *'Hull Type E:' Final drive reduction gear ratio lowered, top speed reduced from 40 to 32 mph. *'Hull Type F:' Driver and Hull Machine Gunner have a side opening safety hatches. The number of track-guard bins is reduced to 2 to make way for the hatches. Turret side bins are added to replace the lost stowage. Hull types D to F apply to Cromwell IV and onwards exclusively. Additional variations were also introduced by some factories. A subset of vehicles had different hatches and/or track tensioners. Vehicles with the alternative track tensioner were predominantly built as Centaur, leading to some confusion on whether this is a Centaur-only feature. Crews in-theatre also experimented with exhaust cowls until a new curved rear cowl was added to the tank specification to prevent exhaust gasses being sucked back into the turret. The chassis of the Cromwell had a wide use in many tanks in the British Army: *'Cromwell Command:' Main gun had been removed. 2 Wireless (No. 19) radio sets were carried (One was high power, the other low power). It was used by Brigade and Divisional HQ (Head Quarters) *'Cromwell Observation Post:' Cromwell IV, VI and VIII, with 2 No.19 Radio Sets and 2 (Portable) No.38 radio Sets. *'Cromwell Control:' Used by Regimental HQ. Had 2 Low Power No.19 Radio Sets *A33 Heavy Assault Tank Excelsior (modified hull and turret) *A30 Cruiser Tank Mk. IX Challenger (modified chassis) *A34 Cruiser Tank Mk. X Comet (modified chassis) *'FV4101 Charioteer:' Postwar design (1950), fitted with a new turret that houses a new ROQF (Royal Ordnance Quick Fire) 20-pounder gun . History George Forty. The Illustrated Guide to Tank of the World. Lorenz Books. (2011). Page 59 Development Development of the Cromwell followed the convergence of two separate projects. The Cromwell tank specification started as an update and replacement for the Crusader tank with a new larger turret. In parallel with development, an uprated engine was in development at Rolls Royce using recovered Merlin engine parts from crashed aircraft. The new engine, named Meteor, produced approximately twice as much power as the earlier Liberty engine fitted to Crusader. Upon successful trials of the new engine in Crusader, the initial Cromwell tank development was halted and the vehicle renamed Cavalier, while the turret was carried forward to a new specification hull capable of supporting the new engine. This became the Cromwell tank. Cromwell offered significant advances in mobility, having both the Meteor engine and the new Merritt Brown steering box/gear box (replacing the earlier Crusader and Cavalier Wilson steering) but the availability of recovered engine parts was limited. New parts manufacturing was dedicated to supplying the need for Merlin aircraft engines. While new manufacturing facilities were created, a number of tanks were fitted with the older Liberty engine. These tanks were designated Centaur. While many Centaurs were converted to Cromwell with new engines when they became available, some continued as Centaurs throughout (and following) the war. While otherwise a success, design of the Cromwell tank highlighted a lack of coordination between the Directorate of Tank Design and that of Armament. The Cromwell turret ring proved 6 inches too small to fit the 77mm gun that was developed at the same time. This caused Cromwell to be fitted with the previous generation 6 pounder (and later 75mm), while the 77mm went into the design specification for the later A34 Comet. To overcome this lack of armament, particularly with the introduction of stronger armoured Axis tanks, the A30 Cruiser Tank Mk. IX Challenger and Sherman Firefly tanks were rapidly developed. Both used the larger 17 pounder anti-tank gun as an interim measure to support the main force of Cromwell and Sherman vehicles. Later Cromwells were also fitted with a sprung towing hook to pull 17 pounder field artillery when required. Production Production was completed by several companies, including Nuffield, Metro-Cammell, L.M.S. Railways, Leylands, Morris Motors and English Electric. Production capacity was limited, and British and Commonwealth forces continued to used the American designed M4 Medium Sherman tank to supplement numbers, forming the majority of the Cruiser tank force until the war ended. Despite the disadvantages, the majority of production used riveted hulls. At the time, a shortage of skilled welders meant that welded production was prioritised onto shipping. When welders were available, the designation of the tank was amended to indicate a welded hull construction. Rivets became a danger to the crews as they could shear off and ricochet upon impact from outside of the vehicle. Service The Cromwell/Centaur entered service in 1944. Centaurs were reserved almost exclusively for training, while production of Cromwells built up to a level where they could enter war use. The Cromwell first saw action in June 1944 in Invasion of Normandy in Operation Overlord. The vehicle was initially equipped to dedicated units of the Desert Rats. Later, units of the Polish and Czechoslovakian Armoured Regiments also received the Cromwell. It was comparable to the Sherman which made up the majority of the other western allied tank force. While it offered a lower silhouette it was significantly more cramped. The low silhouette was highly valued however, and units which later converted to the Challenger complained bitterly of its tall turret, despite it still being lower than the the equivalent Sherman Firefly. The vehicle could not withstand the heaviest Axis tank weaponry however, and on June 13 1944, an entire column of Cromwells and a few Sherman VC Firefly had been ambushed by Michael Whittman's 101st SS Heavy Panzer Battalion. This Heavy Panzer Division consisted of Tiger. A majority of the 27 tanks in the column in the first 15 minutes of the ambush were Cromwells. After World War II, Cromwells remained in use until the 1960's http://www.tanks-encyclopedia.com/ww2/gb/A27M_Cruiser_MkVIII_Cromwell.php. Many Cromwells were converted to the new FV4101 Charioteer with a 20 pdr gun. References Category:British Vehicles Category:Tanks Category:British Tanks Category:Cruiser Tanks Category:A27M Cruiser Tank Mk VIII Cromwell